Effects of Combination Antiretroviral Therapy including Indinavir Sulfate on Coagulation Factors, on Platelet Aggregation and on Factor VIII/IX in HIV-1 Seropositive patients with Hemophilia A or B. The objectives of this protocol are to assess whether, in the specific population being studied, a combined therapy of indinavir sulfate NRTIs induces changes in prospectively identified elements of the coagulation system. It is recognized apriori, that due to the nonfeasibility of having a group in which indinivar sulfate is not added to combination NRTI therapy, it will be impossible to determine what changes in the coagulation system, if any, would have been observed in the absence of indinivar sulfate. However, to help assess changes in the pharmacokinetic half-life and recovery of infused factor VIII, protease inhibitor-experienced HIV-1 seropositive hemophilia A patients will serve as a laboratory control group. We hypothesize that after 12 weeks of treatment, coadministration of indinavir sulfate and NRTIs to protease inhibitor-naive HIV-1 seropositive hemophilia A patients will decrease the pharmacokinetic half-life of infused factor Viii compared to pre-indinavir sulfate therapy baseline relative to changes observed in the laboratory control group. Secondarily, during a 52 week coadministration of indinavir sulfate and combination NTRI therapy to protease inhibitor-naive HIV-1 seropositive hemophilia patients after 12 weeks of treatment: the pharmacokinetic recovery of infused factor VIII in hemophilia A patients will be reduced, relative to changes observed in the laboratory control group; the pharmacokinetic half-life of infused factor IX in hemophilia B patients will be reduced and the pharmacokinetic recovery of infused factor IX in hemophilia B patients will be reduced.